In the normal operation of a four cycle internal combustion engine, it is often considered that about one third of the heat energy is dissipated with the radiator, one third goes out the exhaust, and the remaining third is used to do the work.
The two thirds of the heat not engaged in the working of the engine is wasted energy. Capturing this wasted energy and putting it to use in the working of the engine would increase the fuel efficiency of the engine. This invention proposes a method to recover some of the wasted energy by the use of the turbocharger.
A turbocharger uses the exhaust energy to compress air for use in the combusting of fuel. The increased combustion of fuel causes more exhaust energy, which leads to increased combustion, which leads to increased exhaust. This regeneration cycle causes the increased output to spiral out of control which, if not interrupted, will lead to the destruction of the engine and/or turbocharger.
The normal way to control the output of the turbocharger, is to use a waste gate on the exhaust feed to the turbocharger. The waste gate is correctly named as it bypasses (wastes) exhaust energy. This energy therefore is not returned to the engine.
If a method of internal control could be devised, turbocharger could be allowed to operate at full output without regenerating out of control, therefore returning much more of the exhaust energy back into the operation of the engine in the form of greatly increased manifold pressure.
This high pressure (20+) atmosphere, would propel the sliding surface (piston) within the chamber on the intake cycle. This would amount to a power stroke achieved without the expenditure of fuel.
However, when the sliding surface is at the bottom of the intake stroke, attempting to compress the high pressure contents of the chamber would cancel the gains of the high pressure intake cycle, and possibly damage or destroy the engine.
The proposal of this invention is to vent the high pressure contents of the chamber with the use of the exhaust valve—opening the exhaust valve at approximately bottom dead center, venting the pressure, and closing the exhaust valve with a normal cylinder volume—. The cycles to follow, compression, fuel injection, ignition, power, and exhaust would then be done in a normal manner.